Edge set jack clamp



Oct. 7, 1941. w McK EE.

EDGE SET JACK CLAMP Filed NOV. 28, 1959 x v I/YVE/VTOR. I x753) W NKEE.

H T TOR/YE X Patented Oct. 7, 1941 1 NITED STAT Es PA E Q F C EDGE SET JACK o Aivn' 7 Fred McKee, Long Beach, Calif. Application November 28, 1939, Serial No. 306,502

3 Claims.

clamp, particularly applicable in'the construction of boats, and used particularly for the purpose of placing the hull sheathing or outer planks of the boat in position by pressing these boards or planks tightly together edge to edge, so that they can be properly nailed or otherwise secured to the frame or ribs of the boat.

An object of my invention is to provide a novel edge set jack clamp which can be quickly and easily mounted on the frame or rib members of the hull, and then engage the outer sheathing or planks so as to press these planks tightly against the edge of the adjacent plank for the purpose of nailing or otherwise securing the sheathing or planks in position.

A further object is to provide a novel edge set jack clamp, which can be easily mounted on a rib or frame member of the hull, and. when pressure is applied through the jack screw onto the outer plank or board, an effective wedging action occurs, which will hold the clamp frame against movement while the sheathing is being pressed into position.

Another object is to provide a novel edge set jack clamp of the character stated, which will not mar or otherwise injure either the ribs or the sheathing.

A feature of my invention resides in the ease of attachment or removal of the clamp, and further the eifective manner in which my clamp operates.

Other objects, advantages and features of invention may appear from the accompanying drawing, the subjoined detailed description, and the appended claims.

In the drawing:

Figure 1 is a perspective view of my edge set jack clamp in position on one of the ribs of a boat.

Figure 2 is a rear elevation of my jack clamp.

Figure 3 is a top plan view of the same.

Figure 4 is a side elevation of the same.

Figure 5 is a fragmentary plan view of the back plate, and one of the eye bolts.

Figure 6 is a perspective view of the back plate and the wedge mounted thereon.

Referring more particularly to the drawing, the numeral I indicates a rib or frame member of a boat hull, and 2 the outer planks or sheathing which are secured to the frame or ribs by means of nails, screws or the like. In the construction of a boat, due to the curvature of the hull, the outer planks must be sprung or pressed together in order that their edges may properly meet, and also to enable the mechanic to properly nail or otherwise secure the planks in position. For thepurpose of'pressing these outer planks into position,.I provide anedge set jackclamp 3, which comprises a. head block 4, from each end of which a pin '5 and 6 extends. A back-up strip I is spaced from the head 4 and may, if desired, be in the shape of a channel although other structural shapes may be employed, if desired. A pair of eye bolts 8 and 9 extend between the strip I and the head block 4. The eyes of the bolts 8 and 9 are adapted to fit over the pins 6 and 5 respectively. The eye of the bolt 8 is preferably permanently held on the pin 6, while the bolt 9 can be slipped off of the pin 5 in order to remove the clamp from the rib. The bolts 8 and 9 are pivotally attached to the back-up strip I, by a suitable arrangement 'forexample, a block III, which is pivotally mounted on the strip I, the bolt 9 extending through this block, substantially as shown in Figure 5. Other analogous means of pivotally mounting the bolts 8 and 9 may be employed, if desired.

A nut II is threaded onto each of the bolts 8 and 9 for the purpose of adjusting the distance between the head block and the back-up strip I. A wedge plate I2 is mounted on the head 4, and a second wedge I3 is mounted on the strip I. These wedges are preferably slidably mounted on both the block 4 and the strip I by means of guide bars l4 and I5, which extend through the head 4 and strip I, respectively. These guide bars hold the wedge blocks in proper position, and also permit the strip I and head 4 to slide longitudinally on the wedges, as will be further described.

A jack screw I6 is threaded through the head 4, and bears against a pressure foot IT. This pressure foot bears against an edge of one of the planks 2, substantially as shown in Figure 1. The jack screw I6 is held onto the foot II by means of a suitable clip I8. The clip I8 engages a head l6 on the bottom of the jack screw it, thus holding the jack screw on the foot 11. A handle I9 is pivotally secured to the jack screw it for the purpose of rotating this jack screw and pressing the foot lI tightly against a plank for the purpose of urging the plank into final position.

When the jack clamp is placed on the rib I, the wedges l2 and I3 are pulled upwardly, and the eye of the bolt 9 is swung over the pin 5. The jack screw I6 is now rotated until the pressure foot II bears against a plank. As additional pressure is exerted with the jack screw, the head block 4 will tend to slide upwardly on the wedge l2, as will also the strip 1, on the wedge i3. This will cause the wedges to press tightly against the rib I, and will prevent the clamp from slipping upwardly on the rib. The metal to metal contact of the head block and strip against the Wedges will enable the block and strip to readily slip, while there is considerable friction between the wedges and the wooden rib, which precludes slippage at this point. I have found that the movement between the head block and strip, and the wedges, is relatively slight. Due to the large area of the wedges engaging the rib I, no damage will result to this rib because of the use of my jack clamp.

Having described my invention, I claim:

1. An edge set jack clamp, comprising a head block, a jack screw threaded through the head block, a foot attached to the lower end of the jack screw, a backing strip, means connecting the headblock and the backing strip, said means being detachable to permit removal of the clamp, a wedge plate slidably mounted on the head block and the back strip, a pair of eye bolts connecting the backing strip and the head block, means on the head block engageable by the eye bolts, and means pivotally mounting the bolts on the backing strip.

2. An edge set jack clamp comprising a head block, a jack screw threaded through the head block, a foot mounted on the lower end of the jack screw, a backing strip, a pair of eye bolts connecting the backing strip and the head block, and means on the head block engageable by the eye bolts, and an adjusting nut threaded onto each of the eye bolts, whereby the distance between the head block and the backing strip may be adjusted.

3. An edge set jack clamp comprising a head block, a jack screw threaded through the head block, a foot movably mounted on the lower end of the jack screw, a backing strip, a pair of eye bolts mounted at either end of the backing strip, means on the head block engageable by the eye bolts, a wedge plate mounted on the head block and the backing strip, and guide bars on the wedge plates, said guide bars extending through the head block or the backing strip.

FRED W. McKEE. 

